It's official! The battle for honours in the luxury car market has begun, and BMW is set to fire the first salvo this week by unveiling the all-new 7-Series. The radical machine marks a big departure from tradition for the company. Previous 7-Series model changes have been limited to little more than fresh lights and new alloy wheels.

But this time the firm has ripped up its rulebook with a futuristic mix of technology and styling. Bosses hope the effort will sweep aside rivals such as the Mercedes S-Class and Audi A8, and counter the growing threat from forthcoming challengers such as Volkswagen's D1 and the all-new Jaguar XJ.

As this official debut picture shows, the result is likely to take owners of the current 7-Series by surprise, as the word conservative does not appear to have been included in the design brief. But while details such as the new front lights, flared wheelarches and clamshell bootlid look clever, it's not until you really investigate under the skin of the newcomer that you realise just how much trouble the German manufacturer has gone to in a bid to ensure that this car really is capable of establishing itself as a class leader.

Initially, two new V8 petrol engines will be offered – a 272bhp 3.6-litre engine in the 735i and a 4.5-litre 333bhp unit in the 745i. Both offer improved refinement and 14 per cent better fuel consumption than that of the previous V8 engines, thanks to the Valvetronic technology first employed by the BMW Compact.

The 7-Series will also feature a six-speed automatic transmission, which offers both fully automatic and sequential style shifts. Thanks to all of this, performance from both cars will be impressive. Official figures claim the 745i will sprint from 0-62mph in only 6.3 seconds, while the 735i takes 7.5 seconds. Top speed in both will be limited to 155mph. To ensure all the power is fed seamlessly on to the tarmac, the BMW has pneumatic suspension and electronically controlled dampers, so it should cope easily with even the most demanding roads.

Inside, a new cabin divides the interior into two distinct sections, a 'comfort area' and a 'driving area', as part of a new concept titled iDrive. This means that all of the major controls, including the gear selector and start button, are housed around the steering wheel. Other systems, such as satellite- navigation, air-conditioning and entertainment, are controlled by a single button. By rotating this, the required function can be selected. The idea is to reduce the demands on the driver, leaving them free to enjoy the new model's engine and chassis. Will it work? Watch this space, as we'll be delivering our on-road verdict on the 7-Series very shortly...